Lines Matching +full:performance +full:- +full:affecting
1 # SPDX-License-Identifier: GPL-2.0-only
19 parameter printk.time=1. See Documentation/admin-guide/kernel-parameters.rst
50 int "Default console loglevel (1-15)"
60 Note: This does not affect the log level of un-prefixed printk()
65 int "quiet console loglevel (1-15)"
76 int "Default message log level (1-7)"
82 This was hard-coded to KERN_WARNING since at least 2.6.10 but folks
118 enabled/disabled based on various levels of scope - per source file,
158 nullarbor:~ # echo -n 'file svcsock.c line 1603 +p' >
162 nullarbor:~ # echo -n 'file svcsock.c +p' >
166 nullarbor:~ # echo -n 'module nfsd +p' >
170 nullarbor:~ # echo -n 'func svc_process +p' >
174 nullarbor:~ # echo -n 'func svc_process -p' >
177 See Documentation/admin-guide/dynamic-debug-howto.rst for additional
207 debugging but costs about 70-100K of memory.
225 menu "Compile-time checks and compiler options"
235 # older binutils ports do not support when utilizing RISC-V style linker
238 def_bool $(as-instr,.uleb128 .Lexpr_end4 - .Lexpr_start3\n.Lexpr_start3:\n.Lexpr_end4:)
246 This adds debug symbols to the kernel and modules (gcc -g), and
290 5.0+ accepts the -gdwarf-5 flag but only had partial support for some
294 15-18% savings in resulting image and debug info section sizes as
332 depends on $(cc-option,-gz=zlib)
333 depends on $(ld-option,--compress-debug-sections=zlib)
338 Users of dpkg-deb via scripts/package/builddeb may find an increase in
347 depends on $(cc-option,-gz=zstd)
348 depends on $(ld-option,--compress-debug-sections=zstd)
359 depends on $(cc-option,-gsplit-dwarf)
360 # RISC-V linker relaxation + -gsplit-dwarf has issues with LLVM and GCC
362 # https://github.com/llvm/llvm-project/issues/56642
406 Support for the --lang_exclude flag which makes pahole exclude
420 bool "Allow loading modules with non-matching BTF type info"
436 instance. See Documentation/dev-tools/gdb-kernel-debugging.rst
457 bool "Strip assembler-generated symbols during link"
460 Strip internal assembler-generated symbols during a link (symbols
478 This option will install uapi headers (headers exported to user-space)
481 user-space program samples. It is also needed by some features such
499 - Add the option -fno-inline-functions-called-once to gcc commands.
500 When inlining a function annotated with __init in a non-init
507 bool "Make section mismatch errors non-fatal"
521 address alignment of other domains, and cause magic performance
526 It is mainly for debug and performance tuning use.
549 bool "Compile-time stack metadata validation"
554 Validate frame pointer rules at compile-time. This helps ensure that
570 Selecting this option will pass "-Map=vmlinux.map" to ld
592 bool "Force weak per-cpu definitions"
621 keys are documented in <file:Documentation/admin-guide/sysrq.rst>.
631 to a bitmask as described in Documentation/admin-guide/sysrq.rst.
672 debugfs=[on,no-mount,off]. The restrictions apply for API access
691 Access is off. Clients get -PERM when trying to create nodes in
693 Client can then back-off or continue without debugfs access.
733 properly. This can make kmalloc/kfree-intensive workloads
767 int "debug_objects bootup default value (0-1)"
787 task has ever had available in the sysrq-T and sysrq-P debug output.
818 Enable this to turn on extended checks in the virtual-memory system
819 that may impact performance.
843 bool "Debug VM red-black trees"
846 Enable VM red-black tree debugging information and extra validations.
851 bool "Debug page-flags operations"
901 on the mminit_loglevel= command-line option.
911 debugfs interface under /sys/kernel/debug/notifier-error-inject/memory
916 Example: Inject memory hotplug offline error (-12 == -ENOMEM)
918 # cd /sys/kernel/debug/notifier-error-inject/memory
919 # echo -12 > actions/MEM_GOING_OFFLINE/error
924 be called memory-notifier-error-inject.
935 and decreases performance.
956 mechanism for non-highmem pages and on non-highmem systems.
980 These kinds of bugs usually occur when call-chains in the
1004 memory leaks with a low performance and memory impact.
1109 high-availability systems that have uptime guarantees and
1148 # Note that arch-specific variants are always preferred.
1163 an arch-specific hardlockup detector or if resources needed
1186 The arch-specific implementation of the hardlockup detector will
1236 to determine when a task has become non-responsive and should
1257 high-availability systems that have uptime guarantees and
1274 bool "Report per-cpu work items which hog CPU for too long"
1277 Say Y here to enable reporting of concurrency-managed per-cpu work
1281 them from stalling other per-cpu work items. Occassional
1295 Also it could generate series of lockups with cooling-down periods.
1339 option may have a (very small) performance impact to some
1350 if kernel code uses it in a preemption-unsafe way. Also, the kernel
1391 participant CPUs, tasks and irq-contexts would be needed
1404 and rwsems - in which case all dependencies between these
1409 For more details, see Documentation/locking/lockdep-design.rst.
1412 bool "Enable raw_spinlock - spinlock nesting checks"
1458 bool "Spinlock and rw-lock debugging: basic checks"
1483 injecting additional -EDEADLK wound/backoff cases. Together with
1509 memory-freeing routines (kfree(), kmem_cache_free(), free_pages(),
1562 … Try increasing this value if you hit "lockdep bfs error:-1" warning due to __cq_enqueue() failure.
1585 bool "Locking API boot-time self-tests"
1588 Say Y here if you want the kernel to run a short self-test during
1589 bootup. The self-test checks whether common types of locking bugs
1604 Say Y here if you want kernel locking-primitive torture tests
1756 Enable this to turn on extended checks in the linked-list walking
1759 This option trades better quality error reports for performance, and
1760 is more suitable for kernel debugging. If you care about performance,
1769 Enable this to turn on extended checks in the priority-ordered
1770 linked-list (plist) walking routines. This checks the entire
1779 Enable this to turn on checks on scatter-gather tables. This can
1793 performance, say N.
1817 bool "Force round-robin CPU selection for unbound work items"
1826 round-robin CPU selection to flush out usages which depend on the
1895 in charge of the OHCI-1394 controllers should be used instead.
1897 See Documentation/core-api/debugging-via-ohci1394.rst for more information.
1929 io-memory regardless of whether a driver is actively using that
1934 userspace access to *idle* io-memory ranges (see /proc/iomem) This
1968 interface /sys/kernel/debug/notifier-error-inject/pm
1973 Example: Inject PM suspend error (-12 = -ENOMEM)
1975 # cd /sys/kernel/debug/notifier-error-inject/pm/
1976 # echo -12 > actions/PM_SUSPEND_PREPARE/error
1981 be called pm-notifier-error-inject.
1992 /sys/kernel/debug/notifier-error-inject/OF-reconfig/
1998 be called of-reconfig-notifier-error-inject.
2008 interface /sys/kernel/debug/notifier-error-inject/netdev
2013 Example: Inject netdevice mtu change error (-22 = -EINVAL)
2015 # cd /sys/kernel/debug/notifier-error-inject/netdev
2016 # echo -22 > actions/NETDEV_CHANGEMTU/error
2021 be called netdev-notifier-error-inject.
2026 bool "Fault-injections of functions"
2036 bool "Fault-injection framework"
2039 Provide fault-injection framework.
2040 For more details, see Documentation/fault-injection/.
2043 bool "Fault-injection capability for kmalloc"
2046 Provide fault-injection capability for kmalloc.
2049 bool "Fault-injection capability for alloc_pages()"
2052 Provide fault-injection capability for alloc_pages().
2058 Provides fault-injection capability to inject failures
2062 bool "Fault-injection capability for disk IO"
2065 Provide fault-injection capability for disk IO.
2068 bool "Fault-injection capability for faking disk interrupts"
2071 Provide fault-injection capability on end IO handling. This
2079 bool "Fault-injection capability for futexes"
2083 Provide fault-injection capability for futexes.
2086 bool "Debugfs entries for fault-injection capabilities"
2089 Enable configuration of fault-injection capabilities via debugfs.
2092 bool "Fault-injection capability for functions"
2095 Provide function-based fault-injection capability.
2102 bool "Fault-injection capability for MMC IO"
2105 Provide fault-injection capability for MMC IO.
2112 bool "Fault-injection capability for SunRPC"
2115 Provide fault-injection capability for SunRPC and
2119 bool "Configfs interface for fault-injection capabilities"
2123 This option allows configfs-based drivers to dynamically configure
2124 fault-injection via configfs. Each parameter for driver-specific
2125 fault-injection can be made visible as a configfs attribute in a
2130 bool "stacktrace filter for fault-injection capabilities"
2136 Provide stacktrace filter for fault-injection capabilities
2146 def_bool $(cc-option,-fsanitize-coverage=trace-pc)
2160 for coverage-guided fuzzing (randomized testing).
2162 For more details, see Documentation/dev-tools/kcov.rst.
2167 depends on $(cc-option,-fsanitize-coverage=trace-cmp)
2190 KCOV uses preallocated per-cpu areas to collect coverage from
2218 the kernel command line (when built-in), or from userspace (when
2219 built-in or modular).
2254 Documentation/fault-injection/provoke-crashes.rst
2264 to the KUnit documentation in Documentation/dev-tools/kunit/.
2290 tristate "Array-based sort test" if !KUNIT_ALL_TESTS
2294 This option enables the self-test function of 'sort()' at boot,
2382 tristate "Red-Black tree test"
2385 A benchmark measuring the performance of the rbtree library.
2389 tristate "Reed-Solomon library test"
2395 This option enables the self-test function of rslib at boot,
2405 A benchmark measuring the performance of the interval tree library
2411 Enable this option to build test module which validates per-cpu
2417 tristate "Perform an atomic64_t self-test"
2429 This is a one-shot self test that permutes through the
2431 N-disk array. Recovery is performed with the asynchronous
2527 no compiler warnings from C=1 sparse checker or -Wextra
2534 tristate "Test module for stress/performance analysis of vmalloc allocator"
2540 stress and performance analysis. So, any new change for vmalloc
2541 subsystem can be evaluated from performance and stability point
2572 functions performance.
2583 actual firmware-using device. The contents can be rechecked by
2593 proc sysctl interfaces available to drivers safely without affecting
2611 to the KUnit documentation in Documentation/dev-tools/kunit/.
2628 to the KUnit documentation in Documentation/dev-tools/kunit/.
2646 to the KUnit documentation in Documentation/dev-tools/kunit/.
2648 This is intended to help people writing architecture-specific
2660 to the KUnit documentation in Documentation/dev-tools/kunit/.
2672 to the KUnit documentation in Documentation/dev-tools/kunit/.
2677 tristate "KUnit Test for Kernel Linked-list structures" if !KUNIT_ALL_TESTS
2691 to the KUnit documentation in Documentation/dev-tools/kunit/.
2704 in Documentation/dev-tools/kunit/.
2716 to the KUnit documentation in Documentation/dev-tools/kunit/.
2728 to the KUnit documentation in Documentation/dev-tools/kunit/.
2740 to the KUnit documentation in Documentation/dev-tools/kunit/.
2752 to the KUnit documentation in Documentation/dev-tools/kunit/.
2763 to the KUnit documentation in Documentation/dev-tools/kunit/.
2774 to the KUnit documentation in Documentation/dev-tools/kunit/.
2786 to the KUnit documentation in Documentation/dev-tools/kunit/.
2799 to the KUnit documentation in Documentation/dev-tools/kunit/.
2808 Test if the kernel is zero-initializing stack variables and
2841 This is intended to help people writing architecture-specific
2902 tools/testing/selftests/kmod/kmod.sh --help
2911 virt_to_phys() done against the non-linear part of the
2935 Test if the kernel is zero-initializing heap and page allocations.
2949 Doing so will allow you to run tools/testing/selftest/vm/hmm-tests.
2968 for self-testing floating point control register setting in
3010 memtest=0, mean disabled; -- default
3019 bool "Microsoft Hyper-V driver testing"
3023 Select this option to enable Hyper-V vmbus testing.
3033 Enables rustc's `-Cdebug-assertions` codegen option.
3049 Enables rustc's `-Coverflow-checks` codegen option.
3052 overflow. When overflow-checks are enabled, a Rust panic will occur
3060 bool "Allow unoptimized build-time assertions"
3084 please refer to the KUnit documentation in Documentation/dev-tools/kunit/.